An issue might occur, not allowing you to actually purchase extra SkyDrive storage if you follow this route – be careful:

Get a Microsoft Account, pointing to country X (in my case, Romania);

Get a Windows Phone (in my case, OS version 7), bind it to your Microsoft Account, and its Marketplace to country X too; that will automatically create an XBox Gamertag for you, also bound to country X (assuming that you haven’t used XBox consoles or XBox Live online in the past);

If country X is not supported for XBox Live, Windows Phone Games app will continue to work in a limited fashion; this is as expected;

You can now purchase Windows Phone apps and games from country X’s Marketplace;

If you try to purchase SkyDrive extra storage from SkyDrive.com options, the available subscriptions are listed in country X’s currency (in my case lei – RON), using the Microsoft Payment Hub account generated for country X;

Get an XBox 360 from a retail store; if your country X is not supported as the console’s Locale, you’ll need to choose another (country Y) when you initialize the product (in my case, I selected UK); this is allowed by the agreements, as you can login with your country X XBox Live account (bound to your original Microsoft Account);

XBox console will show you and you can purchase a limited number of games, i.e. only those available in your country X’s marketplace; this is as expected;

To actually buy games, you need to purchase Microsoft points first; when you purchase points, you do that using country X’s currency, using your country X Payment Hub account (bound to your XBox gamertag created originally from your Windows Phone); this is as expected;

However, your purchased Microsoft Points are recorded into a new Payment Hub account (listed as a secondary entry in Microsoft Payment Hub site), bound to country Y, i.e. XBox console’s Locale setting!

At this time, even if in the meantime all you did was to purchase some points on an XBox 360 console using country X currency (RON), if you try to purchase SkyDrive extra storage, the available subscriptions are listed in country Y’s currency (in my case £ – GBP), using the secondary Microsoft Payment Hub account generated for country Y, for which you cannot add credit cards unless you have them issued in country Y; it seems that the most recently created Payment Hub account becomes the default, at least for SkyDrive purchases!

Moreover, it seems there is now way to change country Y selection back to country X, and Microsoft Support cannot do it (at least, yet) either; the Control Panel Region and Language options and/or SkyDrive’s Web site language settings do not help, and neither does selecting a different account on Microsoft Payment Hub Web site (the selection from the menu is not saved to a database, it’s just used for the current Web browsing session).

Microsoft can easily resolve this if they would allow you to select a default Microsoft Payment Hub account on SkyDrive.com Web site, when you go to options and intend to select a subscription to purchase. Alternatively (i.e. better), a Microsoft Payment Hub account should be able to be set as default (for specific features or for features that are not yet bound to any account), such as SkyDrive without any previously purchased subscriptions, on http://commerce.microsoft.com Web site (or at least Microsoft Support should be able to do it for you – it seems that right now they cannot).

Update: I have contacted Microsoft SkyDrive Assistance (Support) on chat, and I reported the issue. They said that they will investigate it and contact me back later (they have asked for my phone number and said they will call me in a few days.) I’ll post an update if/when they reach me, and/or when I get aware of any applied correction for the issue.

Update: Microsoft has just contacted me back (one day after the issue report) and provided a direct solution for this issue: to purchase the SkyDrive options on a specific country market, you need to use a specially configured upgrade link, adding accountid=0 and cptmkt=[culture] parameters to the URL, e.g:https://skydrive.live.com/options/upgrade?accountid=0&ctpmkt=ro-RO